Wiam I. Hussein, MD; Ralph Green, MD; Donald W. Jacobsen, PhD; Charles Faiman, MD
Hussein WI, Green R, Jacobsen DW, Faiman C. Normalization of Hyperhomocysteinemia with L-thyroxine in Hypothyroidism. Ann Intern Med. 1999;131:348-351. doi: 10.7326/0003-4819-131-5-199909070-00005
Download citation file:
Published: Ann Intern Med. 1999;131(5):348-351.
Hyperhomocysteinemia is an independent risk factor for coronary, peripheral, and cerebrovascular disease. Elevated plasma homocysteine levels were described in a preliminary report on primary hypothyroidism.
To determine whether restoration of euthyroidism by L-thyroxine replacement therapy would reduce or normalize plasma homocysteine levels.
Prospective cohort study.
Outpatient endocrinology department of a tertiary center.
14 patients (10 women and 4 men; 25 to 77 years of age): 4 with newly diagnosed chronic (Hashimoto) hypothyroidism and 10 who had been rendered acutely hypothyroid (thyroid-stimulating hormone levelÂ >Â 25 mU/L) by total thyroidectomy for thyroid carcinoma.
Total plasma homocysteine levels were measured at baseline and 3 to 9 months later, after euthyroidism had been attained by L-thyroxine replacement therapy.
Median baseline plasma homocysteine levels in both sexes (women, 11.65 Âµmol/L [range, 7.2 to 26.5 Âµmol/L]; men, 15.1 Âµmol/L [range, 14.1 to 16.3 Âµmol/L]) were higher (PÂ =Â 0.002) than those in healthy female (nÂ =Â 35) and male (nÂ =Â 36) volunteers (women, 7.52 Âµmol/L [range, 4.3 to 14.0 Âµmol/L]; men, 8.72 Âµmol/L [range, 5.94 to 14.98 Âµmol/L]). Eight patients (57%) had baseline plasma homocysteine levels that exceeded the upper limit of sex-specific reference ranges. Upon attainment of euthyroidism, all patients had a diminution in plasma homocysteine levels. The median overall change of âˆ’5.5 Âµmol/L (range, âˆ’15.4 to âˆ’1.8 Âµmol/L) corresponds to a difference of âˆ’44% (range, âˆ’58% to âˆ’13%) (PÂ <Â 0.001). Homocysteine levels returned to normal in 7 of the 8 patients with elevated pretreatment values.
Hypothyroidism may be a treatable cause of hyperhomocysteinemia, and elevated plasma homocysteine levels may be an independent risk factor for the accelerated atherosclerosis seen in primary hypothyroidism.
Learn more about subscription options.
Register Now for a free account.
Endocrine and Metabolism, Thyroid Disorders.
Results provided by:
Copyright © 2016 American College of Physicians. All Rights Reserved.
Print ISSN: 0003-4819 | Online ISSN: 1539-3704
Conditions of Use
This PDF is available to Subscribers Only